Good morning, and welcome to "this week." Country in crisis. A new crackdown in egypt. Could civil war be next for this u.S. Ally? Is there anything america can do to stop it? We're on the ground with breaking details. Republican family feud. Welcome to politics, it's a tough business. Politico calls this the gop's eve of destruction. This morning the party chair is here. And the uproar over stop frisk. Have police gone too far or keeping cities safe? Plus the roundtable on all the week's politics right here this sunday morning. From abc news, "this week" with george stephanopoulos starts now. Good morning. We have brand new developments right now from egypt. After a week of violence that's killed hundreds, injured thousands, the military government now considering a dramatic move, outlawing the muslim brotherhood. But with brotherhood supporters vowing to keep the protests going, it could push egypt to the edge of civil war. Mohammed lila is in cairo with the latest. Good morning. Reporter: Good morning. The mood on the streets is tense, there are police and soldiers and armored personnel carriers on neerl -- nearly every major street. They are bracing for nine more protest marches set to begin within the next hour. Despite the bloody crackdown, the muslim brotherhood is showing its defiance, showing and proving they are willing to fight to the death if it means bringing back the oust the president. Is there a sign that either side is willing to back away and negotiate a solution? Reporter: That's a good question, and this is where it gets dangerous. Both sides see this as an existential conflict. They see themselves as fighting for their very survival. The government and the military say they are fighting terrorists, islamic extremists who are hell-bent on bringing this country to its knees. The muslim brotherhood said they are the legitimate representatives, they won by a slim majority last election. They don't have any middle ground, and many are predicting it will get worse before they get better if they do at all. I'm joined by martha raddatz. This crisis has been unfolding for months, and it's a case-study in u.S. Impotence. When the brotherhood is in, the u.S. Tries to press the brotherhood to open up. They don't. The president condemns the crackdown. That makes no difference either. We seem to have no leverage in egypt. We have seen no change. Everything the u.S. Asks for, nothing happens. That's what's happened over the last few weeks. Military to military, they're trying to influence them, back off, don't go into the camps. They go in and they do it. The president has not taken away, made any indication he will take away the $1.3 billion in military aid, and I don't think you'll see the president try to take that away. They're trying to get a plan together before congress comes back. What do we do, but right now there is no plan or leverage except for military equipment. But you see more cause of senators McCain and graham, saying it's time to suspend aid. And if the military continues, the crackdown, won't the u.S. Be forced into that position? That's the question. Where is the red line for the u.S.? Where is it? There was never a red line in syria, and you see tens and thousands of people killed. They've lost 900 people now in egypt. There still seems to be no red line. We don't know what the u.S. Will do next. I have talked to officials, and they said repair parts for some of the military equipment, perhaps apache helicopters, will that make a difference? They have money from elsewhere. Stand by. We're going to have more from

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